Process for removing fire flash from burned clay product surfaces



Nov. 18, 1952 c. E. MILLER 2,618,109

PROCESS FOR REMOVING FIRE FLASH FROM BURNED CLAY PRODUCT SURFACES Filed Sept. 1, 1950 Ihmcntor Clz arles E Miller %W wmomeg s Patented Nov. 18, 1952 PROCESS FOR REMOVING FIRE FLASH FROM BURNED CLAY PRODUCT SUR- FACES Charles E. Miller, East Palestine, Ohio, assignor of one-half to The Belden Brick Company, Canton, Ohio, a corporation of Ohio Application September 1, 1950, Serial No. 182,725

2 Claims. 1

*The invention or discovery relates in general to processes for removing fire flash from burned clay product surfaces, and in particular to processes for removing fire flash from burner face brick which are made for use in the interior or exterior walls of buildings.

In such a wall of a building made of face brick, it is desirable that the exposed surfaces of the face brick have a substantially uniform color. Face brick are frequently made from a fire clay body. In the production of face brick having a fire clay body, the burning process is carried out in a kiln having a reducing atmosphere which produces a fire flash on the exposed surfaces of the brick stacked in the kiln. This fire flash is an integral part of the exposed surfaces of the face brick, and is characterized by a yellowish brown color when the brick body is fire clay. The other surfaces of such a face brick after burning have a lighter. creamish or grayish color, which is the desired color for all the surfaces of the face brick when laid up in a building wall. In addition to the predominant desired creamish or grayish color, such face brick may have speckled surfaces resulting from dark particles included in the body.

The objects of the present invention or discovery include the provision of novel processes for removing fire flash from burned clay product surfaces so that the surfaces of a face brick or other burned clay unit from which the fire flash is removed will have substantially the same predominant color that is the color of the other surfaces of the burned clay unit.

The foregoing and other objects are attained by the processes for removing fire flash from burned clay product surfaces, and process steps, which" comprise the present invention or discovery, the'nature of which is set forth in the following general statement, and examples of which together with their mode of use are set forth in the following description, and which are particularly and distinctly pointed out and set forth in the appended claims forming part hereof.

The nature of the novel processes for removing fire flash from burned clay product surfaces of the present invention or discovery may be stated in general terms as including the controlled blowing or blasting of a medium hard grade of silica sand of approximately 40-60 mesh against a fire flashed surface of a burned clay unit. The blowing or blasting is carried out at a pressure of between 40 and 60 pounds per square inch. The axis of the blasting sand spray is held to be substantially perpendicular to the fire flashed surfaceof the burned clay unit being treated. The,

nozzle from which the sand blast is ejected is re-,- quired to be to /2 inch in diameter andnot less than A; inch in diameter; It is furthermore required that during the'sand blasting operation the nozzle should be substantially continuously moved laterally and transversely of the surface of the burned clay unit being treated. Likewise; it is necessary to control and maintain the above defined pressure of the sand blast at all times;

during the blasting operation.

While the sand blasting operation .is usually carried out under illumination, it'has been dis-.

covered that when the sand blasting operation as above described is carried out in darkness, ,the

blasting operation produces a flame having a bluish light on the surface of the burned clay unit being blasted, and it is believed that the heat generated by this flame. on and in the fire,

sired fire flash color and render the treated sur-i-.

face substantially the same .as the other surfaces of the burned clay unit not fire flashed, but, with out substantially altering the physical condition of the surface after treatmentexceptingto vre-- move the fire flash color.

By way of example, aface brick is shown bein subject to the sand blasting process of the present invention ordiscovery ,inthe accompanying drawing forming-part hereof, in which the figure is an isometric and diagrammatic view of a face brick and a sand blast nozzle directing a sand blast on a surface of the face brick for carrying out the process of the present invention or dis:

covery.

The face brick is indicated generally by ID and includes an elongated rectangular surface II which is fire flashed after the kiln firing.

For the purposes of carrying out the process of the present invention or discovery, sand blasting equipment including a nozzle I2 is directed by the operator so that the axis indicated by the dot-dash line I3 of the nozzle orifice I4 is perpendicular to the fiat plane of the fire flashed surface I I. The blast of sand I5 issuing from the nozzle orifice I4 is continuously moved, laterally and transversely of the fire flashed surface I I during the treating operation.

The sand used is of a medium hard grade of silica sand of approximately 40-60 mesh. The

When the sand blasting operation of the present invention or discovery is carried out in darkness, it has been discovered that there is produced a flame having a bluish light on the surface ll of the burned clay brick unit [0, and the heat generated by this flame in the fire flashed surface H is believed to be sufiicient to cause a reaction in the surface material constituting the fire flash which removes the fire flash.

The surface I I after being. subject to the above described sand blasting does not have the undesired flre flash color, and has substantially the the surface l I after treatment, excepting that the fire flash color is. removed.

When the body of a face brick is made of fire clay, after the brick is burned, its surfaces which are fire flashed have a yellowish brown color, and the surfaces which are not fire flashed'have a creamish-or grayish color. After being subject to the sand blast treatment of the present invention or discovery, the treated surfaces, previously fire flashed, have the same color as the other surfaces of the brick which are not fire flashed.

When the body of the face brick or other burned clay unit is made of other ceramic material such as shale, or mixtures of shale and fire clay and. other siliceous material, the surfaces not fire flashed have different colors ranging from red to tan, brown, or black, and various color mixtures. The fire flashed surface is usually darker.

The process of the present invention or discovery has been used to advantage, not only on fire clay units, but on other clay units having other bodies such as shale. It is therefore obvious that clay units having bodies made of mixtures of fire clay and shale and other siliceous material may be advantageously treated by the present process.

-The term burned clay unit as used herein throughout the specification and claims is intended to include units made from a ceramic body, such as either a fire clay body, a shale body, or a body of mixtures of fire clay and shale or fire clay and other siliceous material.

I claim:

1. In the manufacture of a burned clay unit the process for removing fire flash from the surface of the burned clay unit which includes blasting the fire flashed surface with sand so as to produce a flame on the blasted fire flashed surface, the flame having a bluish light when the sand blasting is carried out in darkness, and the flame generating heat in the fire flashed surface causing a reaction in the surface. material constituting the fire flash which reaction removes the fire flash, and the surface after the sand blasting having no substantial alteration in its physical condition excepting for the removal of the fire flash, the sand consituting the sand blast being of a medium hard grade of silica sand of approximately 40-60 mesh, and the sand blast having a pressure of between 40 and 60 pounds per square inch, and the sand blast having an axis which is substantially perpendicular to the fire flashed burned clay surface being blasted, and the sand blast being ejected from a nozzle having a bore which is to inch in diameter and not less than inch in diameter.

2. Inv the manufacture ofv a burned clay unit, the process for removing; fire flash. from the surface of the burned clay unit which includes blast ing the fire flashed surface with sand so as to produce a flame on the blasted fire flashed surface, the flame having a bluish light when the sand blasting is carried out in darkness, and the flame generating heat in the fire flashed surface causing a reaction in the surface material con-' stituting the flre flash which reaction removes the fire flash, and the surface after the sand blasting having no substantial alteration in its physical condition excepting for the removal of the fire flash, the sand constituting the sand blast being of a medium hard grade of silica sand of approximately 40-60 mesh, and the sand blast having a pressure of between 40 and 60 pounds per square inch, and the sand blast having an axis which is substantially perpendicular to the fire flashed burned clay surface being blasted, and the sand blast being ejected from a, nozzle having a bore which is to /2 inch in diameter and not less than /4 inch in diameter, and the sand blast being substantially continuously moved laterally and transversely of the fire flashed burned clay surface being blasted.

CHARLES E. MILLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,462,480 Eppler Feb. 22, 1949 FOREIGN PATENTS Num er Country Date 361,895 France Dec. 20, 1906 

